Fig. 3

Mean optical density (OD) in abattoir workers following ELISA for anti-C. burnetii antibodies at Al-Bawadi abattoir. The OD450 values of the positive abattoir workers were grouped into low (n = 7), medium (n = 9) and high (n = 5) based on the intensity. The difference in the intensity of response among the three groups was significant (one-way ANOVA; F(2, 18) = 79.99).